Optimization and Characterization of Nanostructured Surfaces for Photon-Enhanced Thermionic Emission and Photoemission cathodes

PETE vs. Ideal PV PETE vs. PETE+Thermal Theoretical PETE conversion efficiency as a function of Eg and concentration of the direct+circumsolar AM1.5 solar spectrum has been calculated. Each Photon with energy greater than the bandgap is absorbed and creates one electron/hole pair, while sub-bandgap photons are absorbed as heat. Black body radiation losses and transfer, as well as radiative and Auger recombination losses are included. The cathode temperature and electron affinity are chosen to maximize overall efficiency. A PETE device combined with solar thermal could have efficiencies >50%!